Re: [MMUSIC] New Draft: SDP Grouping Identifiers

Martin Thomson <martin.thomson@gmail.com> Tue, 03 December 2013 17:35 UTC

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Date: Tue, 03 Dec 2013 09:35:42 -0800
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From: Martin Thomson <martin.thomson@gmail.com>
To: Paul Kyzivat <pkyzivat@alum.mit.edu>
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Subject: Re: [MMUSIC] New Draft: SDP Grouping Identifiers
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On 3 December 2013 09:19, Paul Kyzivat <pkyzivat@alum.mit.edu> wrote:
> Is there any great need to preserve backward compatibility here?

That's the key question I guess.  The question is whether an offer to
an unknown entity is required to include grouping semantics that a
legacy implementation depends on.  In that sense, having two parallel
grouping mechanisms in an offer is desirable, I think.

In that context, the group-id thing enables an equivalency test.  It's
really quite optional, and given that we are requiring complete
redundancy of the grouping statements, it can be ignored too.

>From my perspective, and I can't speak for Adam here, this group-id
correlation thingy is the only piece of this puzzle that I'm not that
attached to.  We could just have a completely parallel grouping
semantic.  The cost there is that any attempt to maintain and use the
5888 groupings would be impossible once you move to partial offers and
answers.

(I'd rather keep the semantic on in-group, so that group-id remains
optional in this regard.)